Systems for denervation of basivertebral nerves

ABSTRACT

System and methods for channeling a path into bone include a trocar having a proximal end, distal end and a central channel disposed along a central axis of the trocar. The trocar includes a radial opening at or near the distal end of the trocar. The system includes a curveable cannula sized to be received in the central channel, the curveable cannula comprising a curveable distal end configured to be extended laterally outward from the radial opening in a curved path extending away from the trocar. The curveable cannula has a central passageway having a diameter configured allow a probe to be delivered through the central passageway to a location beyond the curved path.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/612,561, filed Sep. 12, 2012, which is a continuation of U.S. patentapplication Ser. No. 12/683,555, filed on Jan. 7, 2010, which is acontinuation-in-part of U.S. patent application Ser. No. 12/566,895,filed on Sep. 25, 2009, which claims priority from U.S. ProvisionalApplication No. 61/100,553, filed on Sep. 26, 2008, the content of eachof which is incorporated herein by reference in its entirety. U.S.patent application Ser. No. 12/683,555 is also a continuation-in-part ofU.S. patent application Ser. No. 11/123,766, filed on May 6, 2005, nowU.S. Pat. No. 7,749,218, which is a divisional of U.S. patentapplication Ser. No. 10/260,879, filed on Sep. 30, 2002, now U.S. Pat.No. 6,907,884, the content of each of which is incorporated herein byreference in its entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC

Not Applicable

NOTICE OF MATERIAL SUBJECT TO COPYRIGHT PROTECTION

A portion of the material in this patent document is subject tocopyright protection under the copyright laws of the United States andof other countries. The owner of the copyright rights has no objectionto the facsimile reproduction by anyone of the patent document or thepatent disclosure, as it appears in the United States Patent andTrademark Office publicly available file or records, but otherwisereserves all copyright rights whatsoever. The copyright owner does nothereby waive any of its rights to have this patent document maintainedin secrecy, including without limitation its rights pursuant to 37C.F.R. §1.14.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention pertains generally to generating passageways throughtissue, and more particularly to creating curved paths in bone.

2. Description of Related Art

Recently, the technique of accessing the vertebral body throughminimally invasive means has been developed through the surgicaltechniques used in vertebroplasty and kyphoplasty. Although accessingthe vertebral segments of the spine through the pedicle and into thelateral/anterior section of the body of the vertebra is the primarymethod of placing a treatment device (e.g. a bone cement delivery deviceand/or an RF probe) into the vertebra, it is difficult to place a probein the posterior midline section of the vertebra. Furthermore, accessingthe posterior midline section of the Si segment of the spine isdifficult with a straight linear access route. A probe preferably needsto be capable of navigating to the posterior section of the Si vertebralbody as well as the same target area within a lumbar vertebral segment.In addition, it is contemplated that spinal segments in the cervical andthoracic spine may also be targeted.

In order to accurately and predictably place a treatment device in theposterior midline section of a lumbar vertebral body or Si vertebralbody, the device or probe needs to navigate to said area through varyingdensities of bone. However due to the varying densities of bone, it isdifficult to navigate a probe in bone and ensure its positioning will bein the posterior midline section of the vertebral body.

Current techniques for tissue aspirations require a coaxial needlesystem that allows taking several aspirates through a guide needlewithout repositioning the guide needle. However the problem with thissystem is that after the first pass of the inner needle in to thelesion, subsequent passes tend of follow the same path within the mass,yielding only blood not diagnostic cells.

A scientific paper written by Kopecky et al., entitled “Side-ExitingCoaxial Needle for Aspiration Biopsy,” describes the use of a sideexiting coaxial needle to allow for several aspiration biopsies. Theguide needle has a side hole 1 cm from the distal tip. When a smallerneedle is advanced through this new guide needle, the smaller needle isdeflected by a ramp inside the guide, causing the smaller needle to exitthrough the side hole. Although this side exiting needle is able todeflect a bone aspiration needle, it does not guarantee that the needleexits the side hole in a linear direction into the tissue site. Once thetissue aspiration needle exits the needle, it will deviate from a linearpath depending on the density of the tissue and inherent materialstrength of the needle. This is an inherent problem the device is unableto overcome.

Accordingly, an object of the present invention is a system and methodfor generating a path in bone that predictably follows a predeterminedcurved path.

BRIEF SUMMARY OF THE INVENTION

The present invention is directed to systems and methods to deploy andnavigate a flexible treatment instrument, such as an RF bipolar probe,within bone. Although the systems and methods described below areprimarily directed to navigating bone through a vertebral member of thespine, and particularly to treat the BVN of a vertebral member, it isappreciated that the novel aspects of the present invention may beapplied to any tissue segment of the body.

The first novel principle of this invention is the ability to navigate acurve or angle within varying densities of cancellous bone and create astraight channel at the end of the navigated curve or angle. Severalsystems are described.

One aspect is a method of therapeutically treating a vertebral bodyhaving an outer cortical bone region and an inner cancellous boneregion, and a BVN having a trunk extending from the outer cortical boneregion into the inner cancellous region and a branches extending fromthe trunk to define a BVN junction, comprising the steps of: a)inserting an energy device into the vertebral body, and b) exclusivelydepositing energy within the inner cancellous bone region of thevertebral body between, but exclusive of the BVN junction and the outercortical bone region, to denervate the BVN.

In another aspect of the present invention, a tube-within-tubeembodiment has a deployable curved Nitinol tube that deploys from astraight cannula. The Nitinol tube is pre-curved to create an angularrange of approximately 0° to approximately 180°, but more specificallyfrom approximately 45° to approximately 110°, when fully deployed fromthe straight cannula. The design of the curve is such that the flexibleelement (carrying the treatment device) can navigate through the angularrange of deployment of the nitinol tube. The curved nitinol tube allowsthe flexible element to navigate through a curve within bone withoutveering off towards an unintended direction. Cancellous bone densityvaries from person to person. Therefore, creating a curved channelwithin varying density cancellous bone will generally not predictably oraccurately support and contain the treatment device as it tries tonavigate the curved channel. With the present invention, the flexibleelement is deployed into the bone through the curved Nitinol tube, whichsupports the element as it traverses through the curve. When it departsfrom the tube, it will do so in a linear direction towards the targetzone. This design allows the user to predictably and accurately deploythe flexible element towards the target zone regardless of the densityof the cancellous bone.

An aspect of the invention is a system for channeling a path into bone.The system comprises a trocar having a central channel and opening atits distal tip, and a cannula sized to be received in said centralchannel and delivered to the distal opening. The cannula has adeflectable tip with a preformed curve such that the tip straightenswhile being delivered through the trocar and regains its preformed curveupon exiting and extending past the distal opening of the trocar togenerate a curved path in the bone corresponding to the preformed curveof the deflectable tip. The cannula comprises a central passagewayhaving a diameter configured allow a treatment device to be deliveredthrough the central passageway to a location beyond the curved path.

In one embodiment, the system further includes a straight styletconfigured to be installed in the trocar, wherein the straight styletcomprises a sharp distal tip that is configured to extend beyond thedistal opening of the trocar to pierce the bone as the trocar is beingdelivered to a treatment location within the bone.

The system may further include a straightening stylet configured to beinstalled in the cannula, wherein the straightening stylet comprising arigid construction configured to straighten the distal tip of thecannula when positioned in the trocar.

In an alternative embodiment, the straightening stylet further comprisesa sharp distal end to pierce the bone, and the straightening stylet andcannula are installed in the trocar in place of the straight stylet asthe trocar is delivered into the bone.

In a preferred embodiment, the system further includes a curved stylethaving an outer radius sized to fit within the central passageway of thecurved cannula. The curved stylet is configured to be installed in thecurved cannula while the curved cannula is extended past the distalopening of the trocar, the curved stylet configured to block the distalopening of the curved cannula while being delivered into the bone.Preferably, the curved stylet has a curved distal end corresponding tothe curve of the curved cannula.

The curved stylet also has a sharp distal tip configured to extend pastthe curved cannula to pierce the bone as the cannula is delivered pastthe distal opening of the trocar. The curved stylet also preferablycomprises an angled distal tip configured to further support andmaintain the curved stylet radius as it is delivered past the distalopening of the trocar and into bone.

Preferably, the curved stylet and the curved cannula have matingproximal ends that align the curve of the curved stylet with the curveof the curved cannula.

In one embodiment, the system further includes a straight channelingstylet configured to be installed in the cannula after removing thecurved stylet, wherein the straight channeling stylet is flexiblydeformable to navigate the curved cannula yet retain a straight formupon exiting the curved cannula, and wherein straight channeling stylethas a length longer than the curved cannula such that it creates alinear path beyond the distal end of the curved cannula when fullyextended.

Another aspect is method for channeling a path into bone to a treatmentlocation in the body of a patient. The method includes the steps ofinserting a trocar having a central channel and opening at its distaltip into a region of bone at or near the treatment location, anddelivering a cannula through said central channel and to said distalopening, wherein the cannula comprises a deflectable tip with apreformed curve such that the tip straightens while being deliveredthrough the trocar and regains its preformed curve upon exiting thetrocar, and extending the cannula past the distal opening of the trocarto generate a curved path in the bone corresponding to the preformedcurve of the deflectable tip. Finally, a treatment device is deliveredthrough a central passageway in said cannula having to the treatmentlocation beyond the curved path.

In one embodiment, inserting a trocar into a region of bone comprisesinserting a stylet into the trocar such that the stylet extends beyondthe distal opening of the trocar, and inserting the stylet and trocarsimultaneously into the region of bone such that the stylet pierces thebone as the trocar is being delivered to a treatment location.

In another embodiment, delivering a cannula through the central channelcomprises inserting a straightening stylet into the central passagewayof the cannula, wherein the straightening stylet comprises a rigidconstruction configured to straighten the curved distal tip of thecannula, and inserting the straightening stylet and straightened cannulasimultaneously into the trocar.

In an alternative embodiment, the straightening stylet further comprisesa sharp distal end to pierce the bone, wherein the straightening styletand cannula are installed simultaneously along with the trocar as thetrocar is delivered into the bone.

In yet another embodiment, extending the cannula past the distal openingis done by inserting a curved stylet into the central passageway of thecurved cannula such that a distal tip of the curved stylet extends to atleast the distal opening of the curved cannula, and simultaneouslyextending the curved cannula and curved stylet from the distal end ofthe trocar such that the curved stylet blocks the distal opening of thecurved cannula while being delivered into the bone.

In a preferred embodiment, the curved stylet has a curved distal endcorresponding to the curve of the curved cannula, and wherein the curvedstylet reinforces the curved shape of the curved cannula as the curvedcannula is extended past the distal opening of the trocar. The curvedstylet has a sharp distal tip such that it is advanced within thecentral passageway so that the curved stylet extends past the distalopening of the curved cannula such that the curved stylet pierces thebone as the cannula is delivered past the distal opening of the trocar.

In a further step, the curved stylet is removed from the curved cannula,and a straight channeling stylet is inserted into the curved distal endof the cannula. The straight channeling stylet is flexibly deformable tonavigate the curved cannula, yet retain a straight form upon exiting thecurved cannula. The straight channeling stylet is longer than the curvedcannula to create a linear channel beyond the distal tip of the curvedcannula.

In a preferred embodiment, the trocar is inserted through a corticalbone region and into a cancellous bone region of a vertebrae, and thecurved cannula is extended though at least a portion of the cancellousbone region to a location at or near the treatment location. A preferredtreatment location comprises a BVN of the vertebrae, and treatment isdelivered to the treatment location to denervate at least a portion ofthe BVN. In one embodiment, a portion of the BVN is denervated bydelivering focused, therapeutic heating to an isolated region of theBVN. In another embodiment, a portion of the BVN comprises is denervateddelivering an agent to the treatment region to isolate treatment to thatregion. Preferably, the treatment is focused on a location of the BVNthat is downstream of one or more branches of the BVN.

Another aspect is a kit for channeling a path into bone. The kitincludes a trocar having a central channel and opening at its distaltip, and a cannula selected from a set of cannulas sized to be receivedin said central channel and delivered to said distal opening. Thecannula has a deflectable distal tip with a preformed curve such thatthe tip straightens while being delivered through the trocar and regainsits preformed curve upon exiting and extending past the distal openingof the trocar to generate a curved path in the bone corresponding to thepreformed curve of the deflectable tip. The cannula comprises a centralpassageway having a diameter configured allow a treatment device to bedelivered through the central passageway to a location beyond the curvedpath, wherein the set of cannulas comprises one or more cannulas thathave varying preformed curvatures at the distal tip.

In a preferred embodiment, the one or more cannulas have a varyingpreformed radius at the distal tip. In addition, the one or morecannulas each have distal tips that terminate at varying angles withrespect to the central channel of the trocar. The length of the distaltips may also be varied. The angle of the distal with respect to thecentral channel of the trocar may vary from 0 degrees to 180 degrees.

The kit may further include a straight stylet configured to be installedin the trocar, the straight stylet comprising a sharp distal tip that isconfigured to extend beyond the distal opening of the trocar to piercethe bone as the trocar is being delivered to a treatment location withinthe bone.

In a preferred embodiment, the kit includes a set of curved styletshaving an outer radius sized to fit within the central passageway of thecurved cannula, wherein each curved stylet is configured to be installedin the curved cannula while the curved cannula is extended past thedistal opening of the trocar. The curved stylet is configured to blockthe distal opening of the curved cannula while being delivered into thebone. Each curved stylet has a varying curved distal end correspondingto the curve of a matching curved cannula in the set of curved cannulas.The curved stylet has a sharp distal tip configured to extend past thecurved cannula to pierce the bone as the cannula is delivered past thedistal opening of the trocar.

In another embodiment, the kit includes a set of straight channelingstylets wherein one of the set of stylets is configured to be installedin the cannula after removing the curved stylet. The straight channelingstylet is flexibly deformable to navigate the curved cannula yet retaina straight form upon exiting the curved cannula. Each of the straightchanneling stylets has a varying length longer than the curved cannulasuch that the straight channeling stylet creates a predetermined-lengthlinear path beyond the distal end of the curved cannula when fullyextended.

Another aspect is a system for channeling a path into bone, having atrocar with a proximal end, distal end and a central channel disposedalong a central axis of the trocar and extending from the proximal endtoward the distal end. The trocar comprises a radial opening at or nearthe distal end of the trocar, the radial opening being in communicationwith the central channel. The system includes a curveable cannula sizedto be received in said central channel and delivered from the proximalend toward said radial opening. The curveable cannula comprises acurveable distal end configured to be extended laterally outward fromthe radial opening in a curved path extending away from the trocar, anda central passageway having a diameter configured allow a probe to bedelivered through the central passageway to a location beyond the curvedpath.

A further aspect is a spine therapy system, comprising: a trocar havinga proximal end, distal end and a central channel; wherein the centralchannel is disposed along a central axis of the trocar and extends fromthe proximal end toward the distal end; wherein the trocar comprises aradial opening at or near the distal end of the trocar, the radialopening being in communication with the central channel; wherein thetrocar is configured to be deployed through a cortical bone region andinto a cancellous bone region of a vertebral body; a curveable cannulasized to be received in said central channel and delivered from theproximal end toward said radial opening; the curveable cannulacomprising a central passageway and curveable distal end configured tobe extended laterally outward from the radial opening in a curved pathextending away from the trocar; wherein the curved path is generatedthough at least a portion of the cancellous bone region of the vertebralbody; and a treatment probe configured to be delivered through thecentral passageway to a location beyond the curved path.

Another aspect is a method for channeling a path into bone to atreatment location in the body of a patient, comprising the steps ofinserting a trocar into a region of bone near the treatment location;the trocar having a having a proximal end, distal end and a centralchannel disposed therebetween; wherein the trocar comprises a radialopening at or near the distal end of the trocar, the radial openingbeing in communication with the central channel; delivering a curveablecannula through said central channel and to said radial opening; anddeploying the curveable cannula laterally outward from the radialopening in a curved path extending away from the trocar

Further aspects of the invention will be brought out in the followingportions of the specification, wherein the detailed description is forthe purpose of fully disclosing preferred embodiments of the inventionwithout placing limitations thereon.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S)

The invention will be more fully understood by reference to thefollowing drawings which are for illustrative purposes only:

FIG. 1 is a system for generating a curved path in bone according to thepresent invention.

FIG. 2 is a sectional view of the system of FIG. 1

FIG. 3 illustrates a sectioned view of a vertebral body with a pathbored through the cortical shell.

FIGS. 4A-F illustrate a method for accessing the BVN with the system ofthe present invention.

FIG. 5 shows an alternative system for generating a curved path in boneaccording to the present invention.

FIG. 6 shows the system of FIG. 5 being installed in a vertebral body.

FIGS. 7A-7B show a curved stylet in accordance with the presentinvention.

FIG. 8 illustrates a perspective view of a system for generating acurved path in bone according to the present invention.

FIG. 9 is an exploded view of the system of FIG. 8.

FIG. 10A-10E show schematic diagrams of the system of FIG. 8 at variousstages of deployment during a procedure.

FIG. 11 is a section view of the proximal end of the system of FIG. 8during introduction of the system into the body.

FIG. 12 is a side view of the distal end of the system of FIG. 8 duringintroduction of the system into the body.

FIG. 13 is a section view of the proximal end of the system of FIG. 8after deploying the curveable cannula into the body.

FIG. 14 is a side view of the distal end of the system of FIG. 8 afterdeploying the curveable cannula into the body.

FIG. 15 is a section view of the proximal end of the system of FIG. 8with the drive nut retracted.

FIG. 16 is a section view of the proximal end of the system of FIG. 8after deploying the probe into the body.

FIG. 17 is a side view of the distal end of the system of FIG. 8 afterdeploying the probe into the body.

FIGS. 18A and 18B are side views of the distal end of the system of FIG.8 with the curveable cannula in a stowed and deployed positionrespectively.

FIG. 19A illustrates a perspective view of an alternative system forgenerating a curved path in bone according to the present invention.

FIG. 19B illustrates the system of FIG. 19A in a deployed configuration.

DETAILED DESCRIPTION OF THE INVENTION

Referring more specifically to the drawings, for illustrative purposesthe present invention is embodied in the apparatus generally shown inFIG. 1 through FIG. 19B. It will be appreciated that the apparatus mayvary as to configuration and as to details of the parts, and that themethod may vary as to the specific steps and sequence, without departingfrom the basic concepts as disclosed herein.

Tube-In-Tube

FIGS. 1 and 2 illustrate a first embodiment of the present inventioncomprising a system or kit 10 for forming a path through bone. Thesystem comprises a having a needle trocar 20 (the main body of theinstrument set). The trocar 20 comprises an elongate shaft 28 having ahandle 24 at its proximal end 32 and a central lumen 36 passing throughto the distal end 22 of the trocar 20. The central lumen 36 is generallysized to allow the other instruments in the system 10 to be slideablyintroduced into the patient to a treatment region. System 10 furthercomprises a straight stylet 80 having a sharp-tipped needle 84 at itsdistal end that is used with the needle trocar 20 to create the initialpath through the soft tissue and cortical shell to allow access to thecancellous bone, a curved cannula 50 that is used to create/maintain thecurved path within the bone/tissue. A straightening stylet 40 is used tostraighten out the curve and load the curved cannula 50 into the needletrocar 20. A curved stylet 60 is used in conjunction with the curvedcannula 50 to create the curved path within the bone/tissue, and achanneling stylet 90 is used to create a working channel for a treatmentdevice (such as RF probe 100) beyond the end of the curved path createdby the curved cannula 50.

The surgical devices and surgical systems described may be used todeliver numerous types of treatment devices to varying regions of thebody. Although the devices and systems of the present invention areparticularly useful in navigating through bone, it is appreciated thatthey may also be used to navigate through soft tissue, or throughchannels or lumens in the body, particularly where one lumen may branchfrom another lumen.

The following examples illustrate the system 10 applied to generating acurved bone path in the vertebral body, and more particularly forcreating a bone path via a transpedicular approach to access targetedregions in the spine. In particular, the system 10 may be used todeliver a treatment device to treat or ablate intraosseous nerves, andin particular that basivertebral nerve (BVN). Although the system andmethods provide significant benefit in accessing the BVN, it isappreciated that the system 10 of the present invention may similarly beused to create a bone path in any part of the body.

FIG. 3 illustrates a cross-sectional view of a vertebra 120. Recently,the existence of substantial intraosseous nerves 122 and nerve branches130 within human vertebral bodies (“basivertebral nerves”) has beenidentified. The basivertebral nerve 122 has at least one exit 142 pointat a location along the nerve 122 where the nerve 122 exits thevertebral body 126 into the vertebral foramen 132.

Preferably, the basivertebral nerves are at, or in close proximity to,the exit point 142. Thus, the target region of the BVN 122 is locatedwithin the cancellous portion 124 of the bone (i.e., to the interior ofthe outer cortical bone region 128), and proximal to the junction J ofthe BVN 122 having a plurality of branches 130 (e.g. between points Aand B along nerve 122). Treatment in this region is advantageous becauseonly a single portion of the BVN 122 need be effectively treated todenervate or affect the entire system. Typically, treatment inaccordance with this embodiment can be effectuated by focusing in theregion of the vertebral body located between 60% (point A) and 90%(point B) of the distance between the anterior and posterior ends of thevertebral body. In contrast, treatment of the BVN 122 in locations moredownstream than the junction J requires the denervation of each branch130.

In one approach for accessing the BVN, the patient's skin is penetratedwith a surgical instrument which is then used to access the desiredbasivertebral nerves, i.e., percutaneously. In one embodiment, atranspedicular approach is used for penetrating the vertebral cortex toaccess the BVN 122. A passageway 140 is created between the transverseprocess 134 and spinous process 136 through the pedicle 138 into thecancellous bone region 124 of the vertebral body 126 to access a regionat or near the base of the nerve 122. It is appreciated that apostereolateral approach (not shown) may also be used for accessing thenerve.

FIGS. 4A-F illustrate a preferred method for accessing the BVN with thesystem 10 of the present invention. First, the straight stylet 80 isinserted in aperture 26 at the proximal end 32 of needle trocar 20. Thestraight stylet 80 is advanced down the central lumen 36 (see FIG. 2) ofthe trocar 20 until the proximal stop 82 abuts against handle 24 of thetrocar 20, at which point the distal tip 84 of straight stylet protrudesout of the distal end 22 of the trocar 20. The tip 84 of the straightstylet 80 preferably comprises a sharp tip for piercing soft tissue andbone.

Referring now to FIG. 4A, the assembly (trocar 20 and straight stylet80) is advanced through soft tissue to the surface of the bone. Once theproper alignment is determined, the assembly is advanced through thecortical shell of pedicle 138 and into the cancellous interior 124 ofthe bone.

After the proper depth is achieved, the straight stylet 80 is removedfrom the trocar 20, while the trocar 20 remains stationary within thevertebrae 120. The straightening stylet 40 is inserted into proximalaperture 52 (see FIG. 2) of the curved cannula 50 and advanced along thecentral lumen of the curved cannula 50 until the stop 42 of the stylet40 abuts up to the proximal end of the curved cannula. This forces thedistal tip of the straight stylet through the curved section 56 of thecurved cannula 50 to straighten out the curve 56. It is contemplatedthat the straight stylet comprise a hard, non-compliant material and thedistal end 56 of the curved cannula 50 a compliant, yet memory retainingmaterial (e.g. Nitinol, formed PEEK, etc.) such that the curved 56section yields to the rigidity of the straightening stylet 40 wheninstalled, yet retains its original curved shape when the stylet 40 isremoved.

As shown in FIG. 4B, once the straightening stylet 40 is secure and thecurved cannula 50 is straight, they are inserted into the needle trocar20 and secured. Proper alignment (e.g. prevent rotation, orient curvedirection during deployment) is maintained by aligning a flat on theupper portion 58 of the curved cannula 50 to an alignment pin securedperpendicularly into the needle trocar 20 handle 24. Once the curvedcannula 50 is secure, the straightening stylet 40 is removed, while thecurved cannula 50 remains stationary within the trocar 20.

Referring to FIG. 4C, the curved stylet 60 is then straightened out bysliding the small tube 68 proximally to distally on its shaft towardsthe distal tip 64 or from the distal tip 64 proximally on its shafttowards the proximal end 62. Once the curved distal tip 66 isstraightened out and fully retracted inside the small tube 68, thecurved stylet 60 is inserted into the proximal aperture 52 of the curvedcannula 50, which still resides inside the needle trocar 20. As thecurved stylet 60 is advanced into the curved cannula 50, the small tube68 is met by a stop 55 (see FIG. 4C). As the curved stylet 60 continuesto advance the small tube 68 is held inside the handle of the curvedcannula 50. This allows the curve of the stylet 60 to be exposed insidethe curved cannula 50. To create the maximum force the curve of the twoparts (50 & 60) must be aligned. To ensure alignment the cap on thecurved stylet 60 has an alignment pin 70 which engages with alignmentnotch 52 on the proximal end of the curved cannula 50.

Once the stylet 60 is fully seated and aligned with the curved cannula50 the tip of the curved stylet 60 will protrude from the tip of thecurved cannula 50 by about 1/16 to 3/16 inches. This protrusion willhelp to drive the curve in the direction of its orientation duringdeployment.

Referring now to FIG. 4D, with the curved stylet 60 and the curvedcannula 50 engaged, the locking nut 58 at the top of the curved cannula50 is rotated counter clockwise to allow the cannula 50 and stylet 60 tobe advanced with relation to the needle trocar 20 such that the proximalend 52 about against 58, advancing the curved cannula 50 and stylet 60beyond the distal opening of trocar 20 to generate a curved path in thecancellous bone region 124. As the curved cannula 50 and stylet 60 areadvanced they will preferably curve at a radius of 0.4 to 1.0 inchesthrough cancellous bone and arc to an angle between 5 and 110 degrees.Once the curved cannula 50 and stylet 60 are deployed to the intendedangle, the locking nut at the top of the curved cannula 50 is engagedwith the needle trocar 20 to stop any additional advancement of thecurved stylet cannula assembly.

Referring to FIGS. 7A-7B illustrate the tip of the curvet stylet 60,which has been formed with two angles. To help the curve deployment inthe proper direction the curve 66 of the curved stylet 60 is shaped in apredetermined orientation. The angle on the inside of the curve 72 isless than the angle on the outside of the curve 74. This disparity inangle helps the stylet cannula assembly 50 & 60 curve in the bone asbone pushes against outside curve face 74 ensuring the curve radius ismaintained during deployment.

Referring now to FIG. 4E, the curved stylet 60 is then removed andreplaced by the channeling stylet 90. The tip 94 of the channelingstylet 90 is advanced beyond the end 54 of the curved cannula 50 towardsthe intended target treatment zone.

Referring now to FIG. 4F, once the channeling stylet 90 reaches thetarget treatment zone, it is removed creating a working channel 146.Channel 140 will generally have a first section 142 that crosses thecortical bone of the pedicle 138, followed by a curved path 144. Thesesections are occupied by curved cannula 50 such that a treatment devicefed through the cannula 50 will have to follow the curve of the cannula50 and not veer off in another direction. The channel may furthercomprise the linear extension 146 in the cancellous bone 124 to furtheradvance the treatment device toward the treatment site T.

With the trocar 20 and curved cannula 50 still in place, a treatmentdevice (e.g. treatment probe 100 shown in FIG. 2, with an active element102 on the distal end 104 of elongate flexible catheter 110 is deliveredto the target treatment location T to perform a localized treatment.

In a preferred embodiment, the active element 102 is delivered to thetreatment site and activated to delivery therapeutic treatment energy.The treatment probe may comprise an RF delivery probe having bipolarelectrodes 106 and 108 that deliver a therapeutic level of heating tostimulate or ablate the nerve 122.

It is appreciated that any number of treatment modalities may bedelivered to the treatment site for therapeutic treatment. For example,treatment may be affected by monopolar or tripolar RF, ultrasound,radiation, steam, microwave, laser, or other heating means.Additionally, the treatment device may comprise a fluid deliverycatheter that deposits an agent, e.g. bone cement, or other therapeuticagent, to the treatment site T. Alternatively, cryogenic cooling may bedelivered for localized treatment of the BVN. Furthermore, treatment maybe affected by any mechanical destruction and or removal means capableof severing or denervating the BVN. For example, a cutting blade, bur ormechanically actuated cutter typically used in the art of arthroscopicsurgery may be used to affect denervation of the BVN.

In addition to or separate from treating the BVN, a sensor may bedelivered to the region to preoperatively or postoperatively measurenerve conduction at the treatment region. In this configuration, thesensor may be delivered on a distal tip of a flexible probe that may ormay not have treatment elements as well.

The goal of the treatment may be ablation, or necrosis of the targetnerve or tissue, or some lesser degree of treatment to denervate theBVN. For example, the treatment energy or frequency may be justsufficient to stimulate the nerve to block the nerve from transmittingsignal (e.g. signals indicating pain).

Once the treatment is complete, the probe 100 is withdrawn. The curvedcannula 50 is then withdrawn into the needle trocar 20. The needletrocar 20 with the curved cannula 50 is then removed and the access siteis closed as prescribed by the physician.

In the above system 10, the design of the curves 56 and 66 of the curvedcannula 50 and curved stylet 60 is such that the flexible element (e.g.carrying the treatment device) can navigate through the angular range ofdeployment of the Nitinol tube of the curved cannula 50. The curvednitinol tube 50 allows the flexible element to navigate through a curvewithin bone without veering off towards an unintended direction.Cancellous bone density varies from person to person. Therefore,creating a curved channel within varying density cancellous bone 124will generally not predictably or accurately support and contain thetreatment device as it tries to navigate the curved channel.

With the system 10 of the present invention, the treatment device 100 isdeployed into the bone through the curved Nitinol tube of the curvedcannula 50, which supports the element as it traverses through thecurve. When it departs from the tube, it will do so in a lineardirection along path 146 towards the target zone. This allows the userto predictably and accurately deploy the treatment device towards thetarget zone T regardless of the density of the cancellous bone.

In some embodiments, a radius of curvature that is smaller than thatwhich can be achieved with a large diameter Nitinol tube may beadvantageous. To achieve this, the curved tube of the curved cannula 50may take one of several forms. In one embodiment, the tube 50 is formedfrom a rigid polymer that can be heat set in a particular curve. If thepolymer was unable to hold the desired curve, an additional stylet (e.g.curved stylet 60) of Nitinol, or other appropriate material, may also beused in conjunction with the polymer tube to achieve the desired curve.This proposed combination of material may encompass and number orvariety of materials in multiple different diameters to achieve thedesired curve. These combinations only need to ensure that the finaloutside element (e.g. trocar 20) be “disengageable” from the internalelements and have an inner diameter sufficient to allow the desiredtreatment device 100 to pass to the treatment region T.

In an alternative embodiment, of the curved cannula 50 may comprise aNitinol tube having a pattern of reliefs or cuts (not shown) in the wallof the tube (particularly on the outer radius of the bend). The patternof cuts or reliefs would allow the tube to bend into a radius tighterthan a solid tube could without compromising the integrity of the tubingwall.

FIG. 5 illustrates a second embodiment of the system or kit 200 of thepresent invention that may be used to reduce the number of stepsrequired for the procedure. The second embodiment includes a needletrocar 20, straightening stylet 40, used with the needle trocar 20 andthe curved cannula 50 to create the initial path through the soft tissueand cortical shell to allow access to the cancellous bone, curved stylet60 used in conjunction with the curved cannula 50 to create the curvedpath within the bone/tissue, and channeling stylet 90 used to create aworking channel for the probe beyond the end of the curved path createdby the curved stylet.

In one method according to the present invention, the straighteningstylet 40 is inserted into the curved cannula 50 and secured. In thisembodiment, the straightening stylet 40 has a sharp tip 46 designed topenetrate bone. Once the straightening stylet 40 is secure and thecurved cannula 50 is straight, they are inserted into the needle trocar20 and secured. In this embodiment, the curved cannula 50 andstraightening stylet 40 are inserted into the shaft 28 of the trocar 20only as far as to have sharp tip 46 of the straightening stylet 40protrude from the distal end 22 of the trocar 20. Proper alignment ismaintained by aligning a flat on the upper portion of the curved cannula50 with a pin secured perpendicularly into the needle trocar 20 handle.

Referring now to FIG. 6, once the curved cannula 50 is secure, theassembly (trocar 20, curved cannula 50, and straightening stylet 40) isadvanced through soft tissue to the surface of the bone. After findingthe proper alignment at the pedicle 138 of vertebrae 120, the assembly(trocar 20, curved cannula 50, and straightening stylet 40) is advancedthrough the cortical shell 128 and into the cancellous interior 124 ofthe bone.

After the proper depth is achieved, the straightening stylet 40 isremoved. The curved stylet 60 is then straightened out by sliding thesmall tube 68 on its shaft towards the distal tip 64. The curved distaltip 66 is straightened out and fully retracted inside the small tube 68,and then the curved stylet 60 is inserted into the curved cannula 50which still resides inside the needle trocar 20. Once the curved stylet60 is inserted into the curved cannula 50, the small tube 68 is met by astop 55 (see FIG. 4C). As the curved stylet 60 continues to advance, thesmall tube 68 is held inside the handle of the curved cannula 50. Thisallows the curve of the stylet 60 to be exposed inside the curvedcannula 50.

To create the maximum force, it is preferred that the curves of the twoparts (50 & 60) are aligned. To ensure alignment the cap on the curvedstylet 60 has an alignment pin, which engages with a notch on the top ofthe curved cannula 50.

When the stylet 60 is fully seated and aligned with the curved cannula50, the tip of the curved stylet 60 will protrude from the tip of thecurved cannula 50 by about 1/16 to 3/16 inches. This protrusion willhelp to drive the curved cannula 50 in the direction of its orientationduring deployment. Once the curved stylet 60 and the curved cannula 50are engaged, the lock nut at the top of the curved cannula 50 is rotatedcounter clockwise to allow the cannula 50 and stylet 60 to be advancedwith relation to the needle trocar 20 (as shown in FIG. 4D). As thecurved cannula and stylet are advanced they generate a curved pathtoward the treatment location T. Once the curved cannula 50 and stylet60 are deployed to the intended angle, the lock nut at the top of thecurved cannula 50 is engaged with the needle trocar 20 to stop anyadditional advancement of the curved stylet cannula assembly.

The curved stylet 60 is then removed and replaced by the channelingstylet 90. The channeling stylet 90 is advanced beyond the end of thecurved cannula 50 (see FIG. 4E) towards the intended target treatmentzone creating a working channel for the active element to be inserted.Once the channeling stylet 80 reached the target treatment zone it isremoved and replaced by the treatment device 100, which is delivered tothe treatment site T and activated.

Once the treatment is complete, the treatment device 100 is withdrawn.The curved cannula 50 is then withdrawn into the needle trocar 20. Theneedle trocar 20 with the curved cannula 50 is then removed and theaccess site is closed as prescribed by the physician.

FIGS.7A and 7B illustrate detail views of a Nitinol wire for the curvedstylet 60 (proximal end not shown). The wire comprises a shaft 78 havingconstant diameter D and a length Ls that may vary according to theapplication and desired depth to the treatment location. The wire has apreformed distal tip that is curved to have a radius r that redirectsthe distal tip 64 at an angle Θ with the shaft. As shown in FIG. 7A,angle Θ is shown to be approximately 110°. However, it is appreciatedthat the preformed tip may have an angle ranging from a few degrees(slight deflection off axis), to up to 180° (e.g. directing back towardthe proximal end).

As shown in FIG. 7B detailing the distal tip 64, the tip may have adistal extension LT that extends away from the shaft 78. To promotechanneling along a path that follows radius r, the distal tip 64 isconfigured with dual-plane bevels 74 and 72. Plane 74 is offset at angleβ, and plane 72 is offset at angle α. This configuration of theleading-allows for the stylet and/or curved cannula to travel throughbone in a path correlating to the specified curve in the stylet and/orcannula.

In the example illustrated in FIGS. 7A and 7B, the curved stylet 60 hasa shaft length Ls of approximately 3.6 in., diameter D of approximately0.040 in., and a distal tip length L_(T) of 0.125 in., radius r of 0.40in., and angle β=35° and angle α=31°. It should be noted that the abovedimensions are for illustration only, and may vary depending on theanatomy and tissue type.

It is appreciated that all the above embodiments may be provided as akit of instruments to treat different regions of the body. For example,the location, orientation and angle of the treatment device with respectto the trocar 20 may be varied by providing a set of instruments atvarying increments. This may be achieved by varying the curvature (56,66) in the curved cannula 50 and curved stylet 60. The curvature may bevaried by varying the radius of curvature r, the insertion depth (shaftlength Ls and tip length L_(T), and/or the final exit angle Θ withrespect to the trocar 20 central bore. Thus, the physician may select adifferent kit for treating a lumber spine segment as opposed to acervical spine segment, as the anatomy will dictate the path that needsto be channeled.

Thus, when treating different spine segments, a set out of the kit maybe selected to match the vertebra (or other region being treated). Forexample, delivering the treatment device at or near the BVN junction fora lumbar vertebra may have a different angle than for a cervicalvertebra, and may vary from patient to patient. The set may be selectedfrom the kit intra-operatively, or from a pre-surgery diagnosticevaluation (e.g. radiographic imaging of the target region).

Tube in Windowed Tube

FIGS. 8-18B illustrate a system 201 for generating a curved path in boneaccording to the present invention. FIG. 8 shows a perspective view ofsystem 201 in a configuration ready for deployment within a patient'sbody. System 201 comprises an introducer/trocar 210 having a proximalend housing 202 coupled to an elongate delivery tube 204. The distal endtip 208 has a sharpened and/or beveled tip to facilitate entry into anddelivery through at least a portion of a bony mass such as the vertebralbody.

The proximal end of the assembly (drive nut 270), may comprise a hard,rigid material to allow the trocar 210 to be tapped into place with amallet or the like.

The tube body 204 comprises a laterally positioned radial opening orwindow 212 disposed just proximal or at the distal tip 208. The window212 provides radial access from the central channel 218 of tube 204 sothat an instrument or probe (e.g. probe 250 distal end) may be deliveredat an angle (e.g. non-axial) with respect to the tube axis or centralchannel 218.

FIG. 9 illustrates an exploded view of system 201 prior to deliverywithin a patient. While it is preferred that the trocar 210 isintroduced to a location near the target treatment site as a wholeassembly shown in FIG. 8, it is also appreciated that the trocar may beintroduced to the location by itself, with the additional componentsbeing positioned once the trocar 210 is in place. In such aconfiguration, a stylet (not shown) may be positioned down the centralchannel 218 of the trocar 204 so as to block the aperture 212 from bonefragments or other tissue matter entering in channel 218. The stylet mayhave a hard, widened proximal end to allow the trocar 210 to be tappedinto place.

The proximal end 206 of trocar housing 202 comprises acentrally-located, counter-bore or recess 216 that is in communicationwith trocar channel 218. Trocar recess 216 allows placement andreciprocation of curveable cannula 230 within the trocar recess 216 andtrocar central channel 218. The curveable cannula 230 may be held inplace at a specified location within the trocar recess 216 via a stopnut 240 that is threaded about proximal body 246 of the curveablecannula 230. The curveable cannula 230 also comprises a central recess268 within proximal body 246 that is centrally aligned with cannulachannel 245. Central recess 268 and cannula channel 245 are configuredto receive and allow reciprocation of probe 250, which is threaded intodrive nut 270.

FIGS. 10A-10E schematically illustrate the system 201 in various stagesof deployment in accordance with the present invention. FIGS. 11, 13, 15and 16 illustrate section views of the proximal end of system 201through the various stages embodied in FIGS. 10A-E. Correspondingly,FIGS. 12, 14, illustrate close-up views of the distal end of system 201through various the stages embodied in FIGS. 10A-E.

FIG. 11 illustrates a sectional view of the proximal end of system 201in an un-deployed state prior to or during insertion of the trocar 210to the desired treatment location in the patient. For delivery into avertebral body 120 (e.g. to access the BVN), the trocar 210 may bedelivered through pedicle 138 via channel 140 (as shown in FIG. 3).Channel 140 may be a pre-drilled hole, or may be generated by insertionof the sharpened tip 208 into the bone. To facilitate insertion, theproximal surface 292 of cap 290 of the drive nut 270 may comprise arigid material (e.g. stainless steel or the like) so that a mallet orsimilar device may strike surface 292 to tap the trocar body 204 intoplace.

During insertion of the trocar 210, the stop nut 240 is threadeddistally along external threads 248 of the proximal body 246 of thecurveable cannula 230 to restrict motion of the cannula 230 distallydown trocar recess 216. This restrained motion keeps the distal end 232of the cannula 230 from prematurely deploying while the trocar 210 isbeing delivered.

As shown in FIG. 12, the distal tip 233 of the curveable cannula 230comprises a series of tubular mating links 234 each having a centralbore to provide a continuous cannula channel 245 along with cannula tube244. Cannula channel 245 extends from central cannula recess 268 of theproximal body 246 to the distal link 232 at tip 233. Distal link 232comprises a beveled tip 233 to facilitate the curveable cannula 230generating a path through bone as detailed below. Distal link 232 mayalso comprise a hard material, e.g. stainless steel or the like toprovide a rigid leading edge for the curveable cannula 230.

The mating links 234 are held together with a cord 242 that runs fromthe proximal body 246 of the curveable cannula 230, and terminates at anaperture 236 in the distal link 232. The distal end of cord 242terminates at a ball 238 that is disposed in a counter-bore,countersink, or like retaining surface of the aperture 236 to retain thecord within the distal link 232.

Referring now to FIG. 10B, once the trocar 210 is in place, stop nut 240is threaded proximally along external threads 248 of the proximal end246 of the curveable cannula 230 to allow motion of the cannula 230distally downward in recess 214.

The proximal body 246 of curveable cannula 230 may then be deployeddownward within trocar recess 216, as shown in section view in FIG. 13.As there may be resistance from the bony mass of the vertebral body (orother bony mass), the cannula 230 may be tapped downward by striking theproximal surface of cap 290 (e.g. with a mallet or the like) whileholding the trocar at housing 202. The motion of proximal body 246pushes tube 244 distally within channel 218 of the trocar body 204. Thisforces the leading edge 232 and trailing mating links 234 out of theradial window 212 in tube 204, as shown in FIG. 14. The distal end ofopening or window 212 comprises a ramp 209 to facilitate the leadingedge 232 out the window 212 at the proper angle with respect to thetrocar tube 204 central axis, and without catching or getting stuck atthe distal end of the trocar.

In addition to the ramp 209, the curved path of the distal tip 233 isfacilitated by tension provided by cord 242, which forces the matinglinks 232, 234 to arch upon the applied tension. The cord 242 is coupledto male-threaded dial 212 (see FIG. 8) to act as a pull cord to applysaid tension. The dial 212 may be turned clockwise or counterclockwisewithin internal-threaded arm 214 to increase or relieve the tension onthe cord 242, thereby providing steering of the distal tip 233 while thecurved cannula 230 is advanced down trocar body 204 and out window 212(e.g. increased tension provides a sharper radius, decreased tensionprovides a more relaxed or no radius.)

Alternatively, cord 242 may comprise a memory material such as a Nitinolwire that fastens the tube 244 and links 232, 234 in a preformedcurved-shape. The cord 246 in this configuration stretches to allow thecurveable cannula 230 to be delivered into and stowed in a linear formwithin channel 218, and retracts when not restrained in channel 218 todrive a curved path when exiting window 212.

As shown in FIGS. 13 and 14, the curveable cannula 230 is fullydeployed, with the proximal end 246 disposed at the bottom of recess216, and the distal tip 233 in a deployed orientation forming a curvedpath (along with trailing links 234) through the bone at the treatmentsite. In this configuration, the probe 250 is restrained from axialmotion (in the distal direction) with respect to the curved cannula 230,because it is threaded inside drive nut 270, which is restrained fromdistal motion by stop 258 in the proximal end 246.

As shown in FIG. 15, the drive nut 270 may be raised (proximallyadvanced out of cavity 268) with respect to the curveable cannula 230and probe proximal body 254 by rotating the drive nut. The proximal body254 of the probe 250 comprises a male thread 256 that mates with thefemale internal threads 262 in a distal recess of the drive nut 270. Thethread pattern 256/262 may preferably be opposite of the thread patternbetween the stop nut 240 and proximal end 246 of the curveable cannula230 (e.g. right-handed thread vs. left-handed thread), so that rotationof the drive nut 270 does not result in rotation of the curveablecannula 230.

Furthermore, the proximal end 254 of the probe 250 comprises a pluralityof vertical groves 264, at least one of which interfaces with key 266 ofthe curveable cannula 230. This interface only allows axial motion ofthe proximal body 264 with the curveable cannula 230, and restrictsrotation of the proximal body 264 with the curveable cannula 230. Thus,rotation of the drive nut 270 only results in proximal translation ofthe drive nut 270. As seen in FIG. 15, the probe proximal body 254 isnow free to move downward in cavity 268.

Referring now to FIGS. 16 and 17, the system 201 is shown in a fullydeployed state, with the probe 250 distal shaft advanced beyond distalend 233 of the curveable cannula central channel 245. This is achievedby advancing the proximal body 254 within the cavity 268 of thecurveable cannula 230. The proximal body 254 and drive nut 270 areadvanced as a unit within cavity 268, preferably by tapping the cap 290,thereby providing an impact force to advance the probe tip 274 out ofthe cannula 230 and through tissue/bone to reach the desired treatmentor diagnostic location within the body.

In an alternative embodiment, a channeling stylet (such as stylet 90shown in kit 10 of FIG. 1) may also be used to create a working channelbeyond the end of the curved path created by the curveable cannula 230prior to deploying a probe for treatment or diagnostic device.

Once the distal tip 274 of the probe 250 is positioned at the desiredlocation, treatment of the target tissue may be performed. As shown inFIG. 17, probe distal end 274 may comprise a first electrode 274configured to deliver a therapeutic amount of RF energy to the targetlocation. In the configuration shown in FIG. 17, the probe preferablycomprises a bipolar probe with return electrode 276, however it isappreciated that the probe 250 may comprise any treatment instrumentdescribed herein.

Cap 290 may further be configured to include (e.g. a self containedunit) a power source (e.g. battery) and receptacles (not shown) tocouple to the probe 250, thereby supplying the energy to deliver atherapeutic level of energy to the tissue. In this configuration, thecap 290 may have sufficient power to deliver one or more metered dosesof energy specifically measured to denervate the BVN of a vertebral bodyin accordance with the present invention.

The cap 290 is preferably treaded (or otherwise releasable coupled) intodrive nut 270 to be interchangeable depending on the application or stepthe procedure of the present invention. For example, a cap 290 having areinforced/hardened surface 292 used for driving the system 201 into thebone may be replaced by another cap having couplings (not shown) forprobe 250, an internal power supply (not shown), or couplings for anexternal power supply/controller (not shown) for delivering energy fortreatment and/or diagnosis of a region of tissue. For embodimentswherein a fluid and/or agent is delivered to the target tissue, the cap290 may be configured to facilitate delivery of the fluid through aprobe having one or more fluid delivery channels.

FIGS. 18A and 18B are side views of the distal end of the system 201with the curveable cannula 230 in a stowed and deployed positionrespectively. The distal link 232 and trailing links 234 are configuredto have mating/interlocking surfaces that allow the distal end of thecannula to curve in one direction. The more distal link of a mating pairwill have an extension 235 that mates with a correspond depression 237in the link proximal to it. This allows the links to rotate with respectto each other to create a curved distal end as shown in FIG. 18B.

FIGS. 19A and 19B illustrate an alternative system 300 for generating acurved channel through bone. System 300 comprises a tubular trocar body302, the proximal end (not shown) of which may comprise a portion or allof any of the previously described proximal ends for devices 10, 200, or201 disclosed herein. The distal tip 334 comprises a leading edgesurface for advancing through bone, and a radial or lateral window 304allowing access to the central channel of the trocar body 302. Thewindow 304 is positioned a short distance proximal to the distal tip334.

A curveable cannula 322 is positioned in the trocar 302, the curveablecannula 322 having a distal end 324 coupled via linkage 326 to apivotable arm 310. The proximal end (not shown) of the curveable cannulamay comprise a portion or all of any of the previously describedproximal ends for devices 10, 200, or 201 disclosed herein. Thepivotable arm 310 has a first end pivotable coupled at joint 314 at alocation at or near the distal tip 334 of the trocar 334. In a stowedconfiguration (illustrated in FIG. 19A), the pivotable arm is configuredto lay axially in the trocar 302 within slot 306 that runs from pivot314 proximally to the radial opening or window 304. The proximal (whenstowed) end 312 of the arm 310 is coupled to the linkage 326.

As shown in FIG. 19B, the cannula 322 may be advanced laterally outwardfrom window 304 by simply advancing the cannula 322 distally down thetrocar 302. The pivotable arm 310 constrains the motion of the curveableend 320 of the cannula to a curved path of specified radius (determinedby the length of arm 310. Once the pivotable arm has reached fullrotation (shown approximately 90 degrees in FIG. 19B, however such anglemay be specified to be any desired amount), the cannula end 320 hascreated a curved path outward from the trocar toward the desiredtreatment site. A probe, stylet or similar device (such as curved stylet60, channeling stylet 90, or probe 100 of FIG. 1) may be positioned atthe opening of the distal end 320 to facilitate generating the curvedbore without allowing tissue or bone to enter the cannula. The probe,treatment/diagnostic device may then be routed through the cannula end320 to a region of tissue/bone that is off-axis from the trocar body302.

It is appreciated that the above systems 201, 300 may be provided as akit of instruments to treat different regions of the body. For example,the location, orientation and angle of the treatment device with respectto the trocar may be varied by providing a set of instruments at varyingincrements. This may be achieved by varying the curvature in thecurveable cannula (230, 320). The curvature may be varied by varying theradius of curvature, the insertion depth (shaft length and tip length,and/or the final exit angle with respect to the trocar central bore.Thus, the physician may select a different kit for treating a lumberspine segment as opposed to a cervical spine segment, as the anatomywill dictate the path that needs to be channeled.

It is appreciated that each of the instruments in the systems 10, 200,201, and 300 detailed above may have any length, shape, or diameterdesired or required to provide access to the treatment/diagnostic region(e.g. intraosseous nerve trunk) thereby facilitating effectivetreatment/diagnostic of the target region. For example, the size of theintraosseous nerve to be treated, the size of the passageway in the bone(e.g. pedicle 138) for accessing the intraosseous nerve, and thelocation of the bone, and thus the intraosseous nerve, are factors thatthat may assist in determining the desired size and shape of theindividual instruments.

The systems 10, 200, 201 and 300 described above may be used with anumber of different treatment modalities for therapeutic treatment ofthe target region. For example, in one embodiment, it is desirable tooperate the treatment devices or probes in systems 100, 200, 20 and 300in a manner that ablates the tissue of the target region (e.g. BVN) toproduce heat as described in U.S. Pat. No. 6,699,242, hereinincorporated by reference in its entirety.

In another embodiment, the treatment device is configured to delivertherapeutic treatment that is targeted to block nerve conduction withoutablating the nerve, i.e. thermal treatment is delivered to the nerve(e.g. via thermal therapy, agent or the like) that results indenervation of the BVN without necrosis of tissue. This may be achievedvia delivery of a lesser amount of energy or agent to the tissue site(either in the form of less exposure time, concentration, intensity,etc.) than is required for ablation, but an amount sufficient to achievesome amount of temporary or permanent denervation.

It is further envisioned that the probed described herein may comprisenon-therapy devices, such as diagnostic devises (e.g. ultrasound,cameras, or the like) to diagnose a region of tissue independent of orin connection with treatment of the region of tissue.

It is also appreciated that individual elements of any of the systems 10200, 201, and 300 detailed above may be used interchangeably whereapplicable. For example, the curved stylet 60 shown in systems 10 and200 may be temporarily implemented in place of the probe of systems 201and 300 to provide additional curving bias to the curveable cannula(230, 320) while the cannula is being driven into the bone. Furthermore,the channeling stylet 90 may be used to further generate a channelbeyond the curved path provided by the curveable cannula (230, 320)

As can be seen, therefore, the present invention includes the followinginventive embodiments among others:

1. A system for channeling a path into bone, comprising: a trocar havinga proximal end, distal end and a central channel; wherein the centralchannel is disposed along a central axis of the trocar and extends fromthe proximal end toward the distal end; wherein the trocar comprises aradial opening at or near the distal end of the trocar, the radialopening being in communication with the central channel; and a curveablecannula sized to be received in said central channel and delivered fromthe proximal end toward said radial opening; the curveable cannulacomprising a curveable distal end configured to be extended laterallyoutward from the radial opening in a curved path extending away from thetrocar; wherein the curveable cannula comprises a central passagewayhaving a diameter configured allow a probe to be delivered through thecentral passageway to a location beyond the curved path.

2. A system according to embodiment 1, wherein the trocar furthercomprises a sharp distal tip configured to pierce through bone togenerate a linear path through bone.

3. A system according to embodiment 2, wherein the curveable cannulacomprises a sharpened distal tip configured to pierce through bone togenerate a curved path extending from a linear path generated by thetrocar.

4. A system according to embodiment 1, wherein the distal end of thecurveable cannula is deformable so as to be delivered in a straightconfiguration through the trocar and deployed in a curved configurationoutward from the radial opening at an angle with respect to the centralaxis.

5. A system according to embodiment 4, further comprising: a pull cordcoupled to the distal tip of the curveable cannula, the pull cordextending to the proximal end of the trocar; wherein the pull cord isconfigured to apply a tensile force to the distal end of the curveablecannula to bias the curveable cannula into a curved configuration.

6. A system according to embodiment 5, wherein the tensile force appliedto the distal tip of the curveable cannula may be controlled from theproximal end of the trocar to steer the curveable cannula along adesired path.

7. A system according to embodiment 4, wherein a distal end of thecurveable cannula comprises a plurality of mating links, the linksconfigured to articulate into a curved shape.

8. A system according to embodiment 4, wherein the central channel ofthe trocar terminates at a ramp leading to the radial window, said rampfacilitating deployment of said curveable cannula outward from saidwindow.

9. A system according to embodiment 1, wherein: the curveable cannulacomprises a proximal end comprising a proximal body wherein the proximalend of the trocar comprises a housing: said housing having a proximalrecess configured to allow reciprocation of the proximal body of thecurveable cannula; wherein the proximal recess is in communication withthe central channel.

10. A system according to embodiment 9, wherein a proximal body of thecurveable cannula is configured to be releasably restrained with respectto translation within the trocar housing.

11. A system according to embodiment 10, further comprising a probesized to fit within the central channel of the cannula; the probecomprising a proximal end configured to be releasably restrained withrespect to translation within the cannula proximal body.

12. A system according to embodiment 11, further comprising a drive nutcoupled to the curveable cannula; wherein the drive nut comprises ahardened proximal surface suitable for applying an impact force toadvance one or more of the trocar, curveable cannula, or probe throughbone.

13. A system according to embodiment 12, wherein the drive nut comprisesa threaded distal recess configured to house the proximal end of theprobe.

14. A system according to embodiment 12, wherein the proximal surface ofthe drive nut comprises an interchangeable cap; said interchangeable capconfigured to provide access to the probe for providing a therapeuticenergy.

15. A method for channeling a path into bone to a treatment location inthe body of a patient, comprising: inserting a trocar into a region ofbone near the treatment location; the trocar having a having a proximalend, distal end and a central channel disposed therebetween; wherein thetrocar comprises a radial opening at or near the distal end of thetrocar, the radial opening being in communication with the centralchannel; delivering a curveable cannula through said central channel andto said radial opening; and deploying the curveable cannula laterallyoutward from the radial opening in a curved path extending away from thetrocar.

16. A method according to embodiment 15, further comprising: deliveringa treatment device through a central passageway in the curveable cannulato a treatment location beyond the curved path.

17. A method according to embodiment 16, further comprising: deliveringa therapeutic amount of thermal energy to the treatment location.

18. A method according to embodiment 17, wherein inserting a trocar intoa region of bone comprises: deploying the trocar through a cortical boneregion and into a cancellous bone region of a vertebral body; whereinthe curved path is generated though at least a portion of the cancellousbone region of the vertebral body.

19. A method according to embodiment 16, further comprising: steeringthe curveable cannula via a pull cord coupled to the distal tip of thecurveable cannula to bias the curveable cannula in the curved path.

20. A method according to embodiment 18, wherein the treatment locationcomprises a BVN associated with the vertebral body, the method furthercomprising: delivering the thermal energy to the treatment location todenervate at least a portion of the BVN.

21. A spine therapy system, comprising: a trocar having a proximal end,distal end and a central channel; wherein the central channel isdisposed along a central axis of the trocar and extends from theproximal end toward the distal end; wherein the trocar comprises aradial opening at or near the distal end of the trocar, the radialopening being in communication with the central channel; wherein thetrocar is configured to be deployed through a cortical bone region andinto a cancellous bone region of a vertebral body; a curveable cannulasized to be received in said central channel and delivered from theproximal end toward said radial opening; the curveable cannulacomprising a central passageway and curveable distal end configured tobe extended laterally outward from the radial opening in a curved pathextending away from the trocar; wherein the curved path is generatedthough at least a portion of the cancellous bone region of the vertebralbody; and a treatment probe configured to be delivered through thecentral passageway to a location beyond the curved path.

22. A system according to embodiment 21, wherein the trocar furthercomprises a sharp distal tip configured to pierce through bone togenerate a linear path through bone.

23. A system according to embodiment 22, wherein the curveable cannulacomprises a sharpened distal tip configured to pierce through bone togenerate a curved path extending from a linear path generated by thetrocar.

24. A system according to embodiment 21, wherein the distal end of thecurveable cannula is deformable so as to be delivered in a straightconfiguration through the trocar and deployed in a curved configurationoutward from the radial opening at an angle with respect to the centralaxis.

25. A system according to embodiment 24, further comprising: a pull cordcoupled to the distal tip of the curveable cannula, the pull cordextending to the proximal end of the trocar; wherein the pull cord isconfigured to apply a tensile force to the distal end of the curveablecannula to bias the curveable cannula into a curved configuration.

26. A system according to embodiment 24, wherein a distal end of thecurveable cannula comprises a plurality of mating links, the linksconfigured to articulate into a curved shape.

27. A system according to embodiment 21, wherein: the curveable cannulacomprises a proximal end comprising a proximal body wherein the proximalend of the trocar comprises a housing: said housing having a proximalrecess configured to allow reciprocation of the proximal body of thecurveable cannula; and wherein the proximal recess is in communicationwith the central channel.

28. A system according to embodiment 27, wherein a proximal body of thecurveable cannula is configured to be releasably restrained with respectto translation within the trocar housing.

29. A system according to embodiment 28, wherein the probe comprises aproximal end configured to be releasably restrained with respect totranslation within the cannula proximal body.

30. A system according to embodiment 29, further comprising: a drive nutcoupled to the curveable cannula; wherein the drive nut comprises ahardened proximal surface suitable for applying an impact force toadvance one or more of the trocar, curveable cannula, or probe throughbone; wherein the drive nut comprises a threaded distal recessconfigured to house the proximal end of the probe; wherein the probecomprises mating threads with the distal recess so as to allowcontrolled translation of the probe with respect to the drive nut.

31. A system according to embodiment 30, wherein the proximal surface ofthe drive nut comprises an interchangeable cap; said interchangeable capconfigured to provide access to the probe for providing a therapeuticenergy.

Although the description above contains many details, these should notbe construed as limiting the scope of the invention but as merelyproviding illustrations of some of the presently preferred embodimentsof this invention. Therefore, it will be appreciated that the scope ofthe present invention fully encompasses other embodiments which maybecome obvious to those skilled in the art, and that the scope of thepresent invention is accordingly to be limited by nothing other than theappended claims, in which reference to an element in the singular is notintended to mean “one and only one” unless explicitly so stated, butrather “one or more.” All structural, chemical, and functionalequivalents to the elements of the above-described preferred embodimentthat are known to those of ordinary skill in the art are expresslyincorporated herein by reference and are intended to be encompassed bythe present claims. Moreover, it is not necessary for a device or methodto address each and every problem sought to be solved by the presentinvention, for it to be encompassed by the present claims. Furthermore,no element, component, or method step in the present disclosure isintended to be dedicated to the public regardless of whether theelement, component, or method step is explicitly recited in the claims.No claim element herein is to be construed under the provisions of 35U.S.C. 112, sixth paragraph, unless the element is expressly recitedusing the phrase “means for.”

1. A system for therapeutically heating a vertebral body to treat backpain, comprising: a bipolar radiofrequency (“RF”) energy delivery devicehaving two electrodes configured to deliver RF energy to a targetlocation of a basivertebral nerve within a vertebral body; a cannulahaving an internal passageway and a distal opening at a distal end ofthe cannula, wherein a distal end portion of the cannula is curved,wherein the diameter of the internal passageway is configured to receivethe bipolar energy device, wherein the distal opening of the cannulaprovides a working portal for the bipolar energy device as it isadvanced past the distal end of the cannula, wherein the curved distalend portion is configured to guide the two electrodes of the bipolarenergy delivery device to the target location, wherein the cannulacomprises polymeric material, wherein the cannula has a lengthsufficient to provide access to the target location within the vertebralbody by the bipolar energy delivery device, wherein the target locationis within an inner cancellous bone region of the vertebral body, andwherein the RF energy is configured to heat the target locationsufficient to denervate a basivertebral nerve at the target location. 2.The system of claim 1, wherein the RF energy is configured to heat thetarget location sufficient to ablate the basivertebral nerve.
 3. Thesystem of claim 1, wherein the RF energy is configured to heat thetarget location sufficient to denervate the basivertebral nerve withoutnecrosis of tissue.
 4. The system of claim 1, wherein the targetlocation is within the inner cancellous bone region of the vertebralbody between, but exclusive of, a basivertebral nerve junction and anouter cortical bone region of the vertebral body.
 5. The system of claim1, wherein the target location is within the inner cancellous boneregion of the vertebral body and proximal to a junction of thebasivertebral nerve.
 6. The system of claim 1, wherein the targetlocation is in a region of the vertebral body located between 60% and90% of the distance between the anterior and posterior ends of thevertebral body.
 7. The system of claim 1, wherein the cannula isconfigured to form a curved path within the inner cancellous boneregion.
 8. The system of claim 1, wherein the curved distal end of thecannula is pre-curved.
 9. The system of claim 7, further comprising atrocar configured to be advanced through an outer cortical bone portionof the vertebral body and into the inner cancellous region, and whereinthe cannula is configured to be inserted through a central lumen of thetrocar and advanced past a distal end of the trocar to form the curvedpath within the inner cancellous bone region.
 10. A system fortherapeutically heating a vertebral body to treat back pain, comprising:an energy delivery device configured to delivery energy to heat a targetlocation of a basivertebral nerve within a vertebral body; a cannulahaving an internal passageway and a distal opening at a distal end ofthe cannula, wherein a distal end portion of the cannula is curved,wherein the diameter of the internal passageway is configured to receivethe energy device, wherein the distal opening of the cannula provides aworking portal for the energy device as it is advanced past the distalend of the cannula, wherein the cannula comprises polymeric material,wherein the cannula has a length sufficient to provide access to thetarget location within the vertebral body by the energy delivery device,wherein the target location is within an inner cancellous bone region ofthe vertebral body, and wherein the energy is configured to heat thetarget location sufficient to denervate a basivertebral nerve at thetarget location.
 11. The system of claim 10, wherein the energy isconfigured to heat the target location sufficient to ablate thebasivertebral nerve.
 12. The system of claim 10, wherein the energy isconfigured to heat the target location sufficient to denervate thebasivertebral nerve without necrosis of tissue.
 13. The system of claim10, wherein the energy delivery device comprises a bipolarradiofrequency probe comprising at least one electrode.
 14. The systemof claim 13, wherein the bipolar radiofrequency probe comprises anactive electrode and a return electrode.
 15. The system of claim 10,wherein the energy delivery device comprises a microwave energy deliverydevice.
 16. The system of claim 10, wherein the energy delivery devicecomprises an ultrasonic energy delivery device.
 17. The system of claim10, wherein the target location is within the inner cancellous boneregion of the vertebral body between, but exclusive of, a basivertebralnerve junction and an outer cortical bone region of the vertebral body.18. The system of claim 10, wherein the target location is within theinner cancellous bone region of the vertebral body and proximal to ajunction of the basivertebral nerve.
 19. The system of claim 10, whereinthe target location is in a region of the vertebral body located between60% and 90% of the distance between the anterior and posterior ends ofthe vertebral body.
 20. The system of claim 10, wherein the curveddistal end of the cannula is pre-curved.